Q: Service Engine light flashing, rough at idle, loss of acceleration, but smooth over 40mph. PCV Valve or hose?

asked by on January 07, 2018

Service Engine light is flashing. Very rough idle and acceleration, but smooth over 40 mph. Unusual smell as well. Pontiac manual says emission system problem. PCV Valve or PCV hose problem?

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Hi Douglas. Thanks for contacting us today. It’s is quite possible that the root source of this issue is a PCV valve or other vacuum leak. Knowing the OBD-II trouble code that is triggering the warning light would be a good way to isolate the damaged components, but an on-site inspection to diagnose this issue is probably a good idea.

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